Reactivation of spent filter materials



mended as well as mixtures of the lnore Patented Apr. 25, 1933 MAX GOEBEL, on linem n, assmNoR TO coMMERoIAIJ sotvnn'rs I {roRA'r'IoNQ 101' 'rnnnn fiAU n mmmA, a CORPORATION: or 'mnYLl Nnw 'fi A i W t '1 m i i i Eni mnnm No Drawing i i A Application filed June '19,

v Mylinventionrelates to the revivification of filtering or decolori zing agents, such. as

fullers I earth, kieselguhr, bauxite, charcoal, and the like,v and especially; decolorizingl clays of the type used in the petroleulngin y" V v,

Various types of fullers earth, othersiliceousbodies such as hydrous magnesium silicates, etc. have been employed for the do colorization. of'oils, both mineral andvegetable, of waxes suchasceresin, Mon-tanwax, etc., and of other liquids Gr mmnsdelta; ily rendered liquid. These clays are rela -v tivcly expensive, and especially inythefp troleum industry are" used in very g'rfeat quantities. The clays, in a finelyf"clivided form, are usedin bulk for treatingiorf fil-v tering the hot oils to remove colored inrpurities by adsorption. After asinglewusc, the clays are found to have lost a large proportion of their adsorbent power, and; the 3 restoration of this power has long been p t I V y a ma't-ic-z hydrocarbons, such .co'm tiounds as problem in the inclustry,-since only a single use of an expensive "clay involves fl'COIlSlflerableitemdn thecostzof refining .In the .past a number. of p'rocesses have been recommended for the revlvihcatlon of.

these clays, butwn'on'e has: met with any degree-vof success. 1 The only 'process to come;

intoepractice is- -that. 0f burning ,the clay. This methodgives very poorreactivation,

with even less success. Such materials :as

pine oil and soap solutions ,haverbeen recorn common organic solvents.) 1

Various organicjsolvents and mixtures of;

solvents have been suggested: byjParsons,

Robinson, Chappjell, Manning, Prutzman',-

and others, However,- the proccsses -suggested by these, investigators involved the:

use of solvent mixturesatpordinary teni-m 'peratures or the use Offfi single solvent;

under greatly increased. 7 temperatures and pressures, and,: as pointed out above, none of these processes have proved satisfactory in actual practice-.

I have now found that greatlyimproved low-boiling petroleum vfraction. 'jlheseaimproved. results i were entirely jfunanticip ted additive results of the mixturesdisclosed "j suit-able, but slightly betterresults are'ob tained "withfnlethy 'zrlc'oliolfand prefer tions,"purityfof the" commercial product, and

' diethyl "ketone, ethyl propylf\ketonefl diaceapparently the alcohol, ketone, andarqmpqic- 1 hydrocarbon serve solvents" for the col the solvents with the clay, "and "to yield; 'a' 4 mixture with the clay which is no t y \cousforei iicient operationk-fi Of (5ourse*the-- jdiluentla lso servessto cl'ieapen the solventcjq w ciency. Ifrtheclay has not been' previously 7 its primary functio results: over thosementionedabovei I obtained by using a solventinixtur'e cont'a mg an alcohol, aketon c body, an mo s hydrocarbon, and a diluent comprisinga in View of the above-mentionedart 'slnce the reactivation :obtainedby the usevof myh solvent is greatly, in eXCeSS of thmpurely 0., in the prior art. i v a (As suitable' alcohols ine'thyl, iethyl; pro pyl, isop'i-opyl, butyl -'a (l ain'yl alc'o'hols are this alcollolalso' in viewer price considera -k g ieater ease of solveiiti lrecovery. Ke'ton bodies such as acetone, niethylethylvketone,

tone alcohol, ancltheflikemay'be employedi Of these I prefer'td use j acetdne. are-' benzol, toluol, etc. are?"satisfactory,but I have found benzol to be preferable. 7 use diluent,- such petroleiunifractions as petro leuln ether, casing-head s' oline, gasoline naphtha, gasoline, "and kerosene are satis-ff factory, but l prefe'rztousemaphthaf 'or gas Tliefmechanics of the, evivificat'io by r] such 'a' sol'vent'mixture are unknowmssbut" ing matter. The diluent apparently i sei-v in a physical capacity, to improve contact of 00' Vise mixture, which isflan added advantage 't be gained without an "apparent,loss i'n eflisubje(.-tedto "aiiiextraction' of the soakageioi' v the diluent will also serve :fas :a solvent for this;oi-lgbutxthis o fflsecondary importanceyci sbeingz to *aid? in. the.

revivification. v. v

The following data .W

the

' provecl results to i be gained byljthe use jof my 1 solvent mixtures over others recommended in the past. Injeach of these cases naphtha was employed as the diluent, and60 c. c.- of

revivified" clay as compared to that treated. withspent clay andfreshclay, v

gi vejrise to improved results, and I preferto ca'rry out-my process atthe-boihng point p course, tem eratures somewhat above or below thei boilmg. oint may-she" employed, but for convenience' and ieflicientoperat on I" prefer to the total solvent mixture were employed for 520' gm. of clay; The percent reactivation s-deiingd'by simple-proportion of the colorimetriciiivalue of oil treated with:- the V Cclorim' I of Per cent 'trentbd 01lreactive-u don Naphthn kpar Mothanol l 35st,, Acetone-d part ing may be, employed. j "I have ound, howoi the v solvent; mixture. Of

reflux the clayl with the solvent; mixture. In this wayf pressure apparatus ',1,S not neces sax-y, and more efficient reactivation is obtained than by;using temperatures below j the boiling point rFurther by refluxing the mixture, lagltation is secured zwhlch 1111110813 necessity of mechan cal "cases; obviates the t mper res h her :tthan tm phe o I those obtained jbylgg entle heating: .is borne out 1; by, a; Vconsiderati'on lof' known adsorption "isobars and: 'isosteres',. which show that "1 at -temperatures ahout 0- ,.C .;.'a-.considerable- {gincjrease in temperature is necessary tofcause a i substantial fl dim1nut1on.;.1n; adsorptive power; 7 The, improved? -results ,Obtlllhgdi in" I-my process 1 are however, not predictable from a mere 'considerationvof these; adsorg tion; curves, since'a -gr'eater' removal of a isorbed or occluded material isrealized at "has the boiling point vof the solvent than could -beanticipatedi froma} calculation based on 7''IQhavej-further found-"that eatly P QWdW mat-Miqbtflm y erry out; the revivification at temperatures considerably above atmospheric; All -PI6Y1911S w processes. for.- reactivation hayejheen carried outlfatls, substantially atmospher c: tempera: ptures -with the exception :of the process of a constant value of-zeta t which'value would ,benearlyconst'ant within the limits I cf temperature under consideration). Other unknown factors appear to be involved. For

example, I 'have'found that the addition of acid to the solvent mixtures, asv recommend-' ed": by Chappell,"}et all, "increases the reacti- .vation 1 at the low, temperatures of the oldprocesses for which the mixtures/were gdev'isfed, b at w emp y ng myP e atthe boiling ,dint'of the-solvent mixture, 1 the addition-alt u H acid has no beneficialefiect, and in man cases is actuall moi-i W 11.1

I 1.5 Naphtha ifnartm v AcetonFwarL x effect may detrimental; :HOWQVQIQI ave-found thatt e-use of high temperatures gives greatly improved resul'ts with most organic-solvent mixtures, and especiallywith-"my preferred m'ii'rtures'. -';The following data-'iwill show the in-j creasedrevivification to beobtained at the boilingypointjof the solvent mixtures Percent i00 ur no until vigorous refluxing commences, and the be'usedwin ".makingf-fup'f the next bate freflux'is continued jot-1hr. Thesolvent ex tract isv then drawn offiiand 300 gals. 'of

' t pr ve r es l eeer q o ned a 1 naphtha added :to remove i the remainder of the esolveritZ-z, Thenaphtha. is their wdrawn oil, and 'the la'st traces rer'n'oved by steam adistillationlfieThe naphtha ma of solvent' mixtureg if, desired." The clay may then be dried,.or ma beflused for the I decolorization oi ayfresh atc'hofoil while still? in a mudded c'ondition. The solvents'f ,i} 1 are recovered by distillation from the sol-1 ,1

vent extract; "andlinay'thenbeyused for fur-1 'ther"revivificationm-If'the spentbclay -has not previously-extracted with naphtha or another oil'solvent remove the-soak age oil ,this"iwi ll be} in the. residue of the solvent extract after recovery of the solvents. This oil may be acid-treated and added to a fresh batch of crude oil; or, if an asphalt-crude is being employed it may be addeddirectly to the crude oil since it will receive the acid-treatment in the process.

Of course, the above procedure may "be varied in a number of ways without departing from the spirit of my invention. For example, the time of refluxin will depend upon the size of the batch, t e amount of coloring matter in the clay, and other factors. I have found, however, that in general 15 min. to 2 hrs. is suflicient for this purpose. The separation of the solvent extract from the clay may be' accomplished by any of the known means such as filtration,

\Vhile I have found that in most cases a.

nized cycle, a. counter-current extractionusing a boiling solvent mixture could easily be made; I y The amount of solvent mixture to be-used per lb. of clay will, of course,-depend upon the size of the particles, the amount ofoil 45 or coloring matter .in the clay,and generally upon its tendency to form a thick mud' rather than a slurry of more desirable consistency-for extraction. In general, I have found thelower limit of solvent mixture of of cla 4 The upper limit will of course be fixed y price considerations.

I have found that the exact proportions of the ingredients of the solvent mixture compound of each of the types specified is present in a substantial amount, say 5 or of the total. When the ratio of total,

centrifuging, decanting, blowing, etc. The

sirable, repeated or continuous extraction clay to be about l'gal. of-solventsto 2 lbs.

are not of greatimportance, so. long as the I I prefer to use the diluent amounts of from %;to of the total. The mixture used inthe example cited above has proved very satisfactory for a number of. different clays. 1 H

It is to be understood that I doj-not wish my invention to be limited to any of the specific substancesor amountsycited in the exmp or ta l s i i .WhatI claimisp,

1. A processfor the revivification of spent decolorizing agents which comprises extracting with asolvent mixture comprising an alcohol, aketonic body, an aromatic hydrocarbon, and a diluent comprising a lowboiling petroleum fraction.

2. A rocess for the revivificationof spent decolorizing agents which comprises extracting with a solvent mixture comprising an aliphatic alcohol, a. ketone, benzol, and a diluent comprising a low-boiling petroleum fraction.

3. A process for therevivification of spent 'decolorizing agents which comprises, ex tracting with a solventv mixture comprising an alcohol, a ketonic body, an aromatic hydrocarbon, and at least'25% ofa diluent comprising a low-boiling petroleum 'fraction.

4. A process for the revivification of spent decolorlzing agents which comprises extracting with a solvent mixture comprising methanol, acetone, benzol and naphtha.

5. A process for the revivificationof spent decolorizing agents which comprises extracting with a solvent mixture comprisin methanol, acetone, benzol, and at least 25 o of a diluent comprising a low-boiling petroleum fraction.

. decolorizing a nts which comprises extracting with afifoilingsolvent mixture comprising an alcohol, a ketonic body, an aromatic hydrocarbon, and a diluent cornpris ing a low-boiling petroleum fraction.

7 A process for the revivification of spent decolorizing agents which comprises. re-' fluxing with a solvent mixture comprising an alcohol, a ketonic body, an aromatic hyf.

drocarbon, and a diluent: comprising a' low- 118 'boilingfpetroleu'm fraction.

8. A process for the revivification ofsp'ent 1 decolorizing agents which 'comprises:re-,Q fiuxing for from 15 to 2 hrs. with a. solvent mixture comprising an alcohol ,a ke- I130 tonic body, an aromatic drocarbon, and a diluent comprising a lowiling petroleum fraction. i i l '9. A recess for the'revivification of spent decolorizin agents which; comprises re- 125 fluxing wit a solvent mixture comprising an aliphatic alcohol, a ketone, benzol,'and at least 25% of a diluent comprising a lowboiling petroleum fraction. j 1

10. A process for the revivification of 0 6. A process for the revivification of spent I A 7 spent decolol izingagents which comprises refll lx'in'g with 'a; solventmixture comprisingimethanol;aceti1e,'benz0l, and at least 25% I of a diluent comprising low-boiling p'et1'0 Eleum fraction 11. A process for the revivification of 'spent' decolorizing *agents whichpomprises refluxing witlrafsolvent mixture comprising one "part methanol, one part-acet0ne,- one 10 part benzol, andvthree parts-naphtha."

Inftestimony whereo Y GOEBEL. 

